The Bonner Durchmusterung (BD) is a visual survey of stars in the declination zones 89 deg to -01 deg. This volume contains the data for the declination range 89 deg to 30 deg. The survey, completed by Argelander and his assistants in the years 1852-1861, was performed and the stars cataloged by allowing the telescope to drift along the mean declination of each zone and recording the positions and magnitudes of stars crossing the transit line of each field. The goal of the survey was to obtain a position and estimated visual magnitude for every star visible with the 78-mm Bonn telescope. Actual magnitude estimates were made and reported to 0.1 mag for all stars down to 9.5 mag, with fainter stars being assigned to 9.5. The positions are given to 0.1 s in right ascension and 0.1 min in declination for the equinox 1855. No corrections or changes were incorporated into the original data, except those listed (e.g., no changes were introduced from more modern positions and magnitudes or from comparison with other catalogs).